<?php
class Race
{   
    protected $_buildings;
    protected $_name;
    
    public abstract function isPlayable();
    
    public final function name()
    {
        return $this->_name;
    }

    public final function buildings()
    {
        return $this->_buildings;
    }
}

class PlayableRace
{
    public function isPlayable()
    {
        return true;
    }
}

class NpgRace
{
    public function isPlayable()
    {
        return false;
    }
}
?>
